以斜发沸石为原料制取壳聚糖改性沸石,并对改性沸石进行扫描电镜( SEM)和孔分布表征.改性沸石的表面附着壳聚糖并形成覆盖性多孔状结构,改性前后沸石BET比表面积变化不大,但改性沸石的总孔容积和平均孔径分别增大1.62倍和1.71倍.相对而言,初始浓度变化对天然沸石去除率的影响较小,而改性沸石所受影响较大.沸石对MG的吸附速率明显低于LR,吸附容量明显大于后者,这可能是范德华力和静电斥力综合作用的结果.pH值在2.0—9.0范围内MG的吸附随pH呈上升趋势,pH值超过9.0后又略有下降,LR在pH 4?0—11?0范围内呈下降趋势.反应温度从20℃上升至60℃,天然沸石对LR和MG的吸附容量有所提高.相对于准一级和准二级方程,孔内扩散方程可以更好地描述MG、LR在沸石和改性沸石上的吸附动力学,说明吸附反应主要发生在较大的微孔中,孔内扩散为影响吸附反应速率的主要因素. Langmuir 方程和Freundlich方程均能较好描述吸附等温过程,两种沸石均易于与MG和LR发生吸附反应,但改性沸石吸附能力明显优于前者.热力学分析表明,MG和LR在沸石和改性沸石上的吸附过程是吸热反应,吸附反应是自发的过程,且属于物理吸附为主的反应类型.
Modified zeolite was synthesized using natural zeolite ( clinoptilolite) and chitosan. The SEM and nitrogen adsorption experiments were carried out to characterize the surface structure. Results indicated that zeolite surface was covered with chitosan and porous structure was formed. There was no significant difference of the BET specific area before and after modification. But the total pore volume and mean pore size were increased by 1.62 and 1.71 times respectively. The initial concentration had more effect on the modified zeolite than natural zeolite. Adsorption of MG onto zeolites was slower than that of LR, and the adsorption capacities of MG were much higher than that of LR. The adsorption was probably due to the combined effect of Vander Waals′ force and electrostatic repulsion. The adsorption of MG increased with pH in the range of 2. 0 and 9. 0, but dropped appreciably when pH was above 9. 0? The adsorption of LR decreased when pH increased between 4.0 and 11?0? The adsorption capacities of MG and LR onto natural zeolite and modified zeolite increased with temperature from 20 ℃ to 60 ℃. The adsorption kinetics conformed to pore?diffusion reaction much more closely than first?order or second?order reaction, which meant the adsorption took place in rather large pores and diffusion in pores was the key step to determine adsorption velocity. Langmuir equation and Freundlich equation could describe adsorption isotherm satisfactorily. Natural and modified zeolite could easily absorb MG and LR when judged by 1/n value. Results of thermodynamics analysis indicated that adsorptions of MG and LR on zeolites were endothermic reactions. The adsorption reactions were spontaneous and mainly belong to physical adsorptions.
参考文献
[1] | Jose Blanco;Francesc Torrades;Moises Moron.Photo-Fenton and sequencing batch reactor coupled to photo-Fenton processes for textile wastewater reclamation: Feasibility of reuse in dyeing processes[J].Chemical engineering journal,2014:469-475. |
[2] | Huifang Wu;Shihe Wang .Impacts of operating parameters on oxidation-reduction potential and pretreatment efficacy in the pretreatment of printing and dyeing wastewater by Fenton process[J].Journal of hazardous materials,2012(Dec.):86-94. |
[3] | Yang, Q.;Wang, J.;Wang, H.;Chen, X.;Ren, S.;Xu, Y.;Zhang, H.;Li, X..Evolution of the microbial community in a full-scale printing and dyeing wastewater treatment system[J].Bioresource Technology: Biomass, Bioenergy, Biowastes, Conversion Technologies, Biotransformations, Production Technologies,2012:155-163. |
[4] | Sheng-Jie You;Dyi-Hwa Tseng;Jun-Yu Deng .Using combined membrane processes for textile dyeing wastewater reclamation[J].Desalination: The International Journal on the Science and Technology of Desalting and Water Purification,2008(1/3):426-432. |
[5] | 刘永涛,艾晓辉,索纹纹,杨秋红.浸泡条件下孔雀石绿及其代谢物隐色孔雀石绿在斑点叉尾组织中分布及消除规律研究[J].水生生物学报,2013(02):269-280. |
[6] | 吴学立,吴永宁,赵云峰,袁宗辉.液相色谱-线性离子阱质谱法检测草鱼中孔雀石绿、结晶紫及其代谢产物[J].中国食品卫生杂志,2007(03):209-214. |
[7] | Zahn T;Braunbeck T .Cytotoxic effects of sublethal concentrations of malachite green in isolated hepatocytes from rainbow trout (Oncorhynchus mykiss)[J].Toxicology in Vitro,1995,9(5):729-741. |
[8] | Andrea Schuetze;Thomas Heberer;Susanne Juergensen .Occurrence Of Residues Of The Veterinary Drug Malachite Green In Eels Caught Downstream From Municipal Sewage Treatment Plants[J].Chemosphere: Environmental toxicology and risk assessment,2008(11):1664-1670. |
[9] | 朱丰华,任刚,李明玉,林达红,王建平,林浩添.改性沸石去除微污染水中氨氮的试验[J].暨南大学学报(自然科学与医学版),2010(03):286-289,298. |
[10] | 孙帅,李明玉,任刚,曹刚,宋琳,谭铭卓.改性沸石粉吸附去除微污染水中Ni(Ⅱ)的试验研究[J].生态科学,2013(03):351-354. |
[11] | Shaogang Liu;Yuqiu Ding;Pengfei Li.Adsorption of the anionic dye Congo red from aqueous solution onto natural zeolites modified with N,N-dimethyl dehydroabietylamine oxide[J].Chemical engineering journal,2014:135-144. |
[12] | Cottet L;Almeida C A P;Naidek N et al.Adsorption characteristics of montmorillonite clay modified with iron oxide with respect to methylene blue in aqueous media[J].Applied Clay Science,2014,95:25-31. |
[13] | A.A. Elabd;W.I. Zidan;M.M. Abo-Aly;E. Bakier;M.S. Attia .Uranyl ions adsorption by novel metal hydroxides loaded Amberlite IR120[J].Journal of environmental radioactivity,2014(Aug.):99-108. |
[14] | Saikia Jiban;Das Gopal .Framboidal vaterite for selective adsorption of anionic dyes[J].Journal of Environmental Chemical Engineering,2014(2):1165-1173. |
[15] | 谭艳芝,王秀芳,钟国英.新型竹活性炭对水体违禁药物孔雀石绿吸附性能的影响[J].中南大学学报(自然科学版),2010(04):1287-1291. |
[16] | 张建,陈素红,张成禄,邱宪锋,孙丰凯,徐景涛.水枝锦活性炭对孔雀石绿的吸附性能研究[J].环境污染与防治,2009(03):1-5,20. |
[17] | 俞洁,郑继东,牛韩根,李芸,张雅迪,潘元沛.聚(丙烯酰胺-co-丙烯酸)水凝胶对孔雀石绿的吸附研究[J].水处理技术,2012(11):59-64. |
[18] | 高如琴,郑水林,刘月,许辉,王彩丽.硅藻土基多孔陶瓷的制备及其对孔雀石绿的吸附和降解[J].硅酸盐学报,2008(01):21-24,29. |
[19] | 王艳,苏雅娟,李平,刘博.绿茶微粉对染料亚甲基蓝和孔雀石绿的吸附研究[J].中国食品学报,2011(04):83-89. |
[20] | 司春英,高景峰,张志红.改性黄豆粕对废水中Cu2+的生物吸附特性[J].安全与环境学报,2013(05):44-51. |
[21] | Mcmurry John.Fundamentals of organic chemistry[M].American:Brooks/Cole,7 International ed,2010:336-351. |
[22] | Kadirvelu K.;Kalpana R.;Rajeswari S.;Palanival M. .Activated carbon from an agricultural by-product, for the treatment of dyeing industry wastewater[J].Bioresource Technology: Biomass, Bioenergy, Biowastes, Conversion Technologies, Biotransformations, Production Technologies,2000(3):263-265. |
[23] | George Z. Kyzas;Margaritis Kostoglou;Alexandros A. Vassiliou .Treatment of real effluents from dyeing reactor: Experimental and modeling approach by adsorption onto chitosan[J].Chemical engineering journal,2011(2):577-585. |
[24] | 王宁,侯艳伟,彭静静,戴九兰,蔡超.生物炭吸附有机污染物的研究进展[J].环境化学,2012(03):287-295. |
[25] | Guo, J.;Chen, S.;Liu, L.;Li, B.;Yang, P.;Zhang, L.;Feng, Y..Adsorption of dye from wastewater using chitosan-CTAB modified bentonites[J].Journal of Colloid and Interface Science,2012:61-66. |
[26] | Yang Qin;Zhang H J .Discussion on the gaseous slip model based on Langmuir adsorption isotherm[J].Physics Procedia,2012,32:179-183. |
[27] | Song, X.;Zhang, Y.;Yan, C.;Jiang, W.;Chang, C..The Langmuir monolayer adsorption model of organic matter into effective pores in activated carbon[J].Journal of Colloid and Interface Science,2013:213-219. |
[28] | Ali Fakhri;Saeideh Adami .Adsorption and thermodynamic study of Cephalosporins antibiotics from aqueous solution onto MgO nanoparticles[J].Journal of the Taiwan Institute of Chemical Engineers,2014(3):1001-1006. |
[29] | Manasi;Vidya Rajesh;N. Rajesh.Adsorption isotherms, kinetics and thermodynamic studies towards understanding the interaction between a microbe immobilized polysaccharide matrix and lead[J].Chemical engineering journal,2014:342-351. |
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